Non-oxidative activation of methane under a pulsed mode in the presence of supported platinum-containing catalysts

Abstract

The novelty of the research was that the transformations were carried out in a pulsed mode at small contact times. A rise in temperature increases the amount of activated methane but decreases the H/C ratio in the surface hydrocarbon fragments. The optimal contact time of methane with the catalyst is in the range from 1 to 2.5 s. It provides the required methane activation depth and, which is most important, the optimal H/C ratio in the surface hydrocarbon fragments CHx equal to 3 at./at. An increase in the amount of strong LAS (a.b. at 2200 cm−1 and higher) in the support enhances methane activation at a considerable decrease in the H/C ratio in the surface hydrocarbon fragments, whereas a substantial increase (in the case of Pt/Al2O3−F, up to 150 μmol/g) deteriorates the activity toward methane activation and the H/C ratio.The novelty of the research was that the transformations were carried out in a pulsed mode at small contact times. A rise in temperature increases the amount of activated methane but decreases the H/C ratio in the surface hydrocarbon fragments. The optimal contact time of methane with the catalyst is in the range from 1 to 2.5 s. It provides the required methane activation depth and, which is most important, the optimal H/C ratio in the surface hydrocarbon fragments CHx equal to 3 at./at. An increase in the amount of strong LAS (a.b. at 2200 cm−1 and higher) in the support enhances methane activation at a considerable decrease in the H/C ratio in the surface hydrocarbon fragments, whereas a substantial increase (in the case of Pt/Al2O3−F, up to 150 μmol/g) deteriorates the activity toward methane activation and the H/C ratio.